The field of high-energy physics endeavors to identify various sub-atomic particles, such as hadrons. There are two techniques presently used to distinguish hadrons at colliders. The first technique uses Cherenkov counters to distinguish particles by the dependence of Cherenkov angle on velocity. See T. Iijima et al., Nucl. Instrum. Meth. A453:321-325, 2000; see also I. Adam et al., Nucl. Instrum. Meth. A538:281-357, 2005. In the limited path length available in a cylindrical collider experiment, the first technique has several limitations including being applicable only for momenta up to a few GeV and requiring significant radial space. The second technique is time-of-flight, in which the transit time from creation of the particle to an outer ring of detectors is measured. The second technique may also provide the velocity of the particle. The typical time resolution using the detectors of the second technique is 110 psec. See C. Paus et al., Nucl. Instrum. Meth. A461 :579-581, 2001. In both techniques combining the velocity measurement with the momentum measurement in the magnetic spectrometer, one may measure the mass of the particle, and hence its identity (e.g., pion or kaon).
A need exists to identify various sub-atomic particles without the limitations of prior techniques.